Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

As far as I understand (with Avid, other software may have other requirements) a faster CPU with less cores is better than a slower CPU with more cores, but a dual processor system should perform better than a comparable (as for the core number) single CPU box. It's not only a matter of clock and cores, it's also the CPU class, Xeon on a dual processor workstation, and the architecture of the motherboard itself. I's workstation class components versus consumer class (and there are many flavours of consumer parts!). That being said, unless You do effects intensive stuff with heavy rendering and plenty of video tracks, You'll be fairly happy with a latest i7 or i9 CPU, provided that You invest on a Quadro card and the more RAM You can fit in the motherboard; OTOH You may find that a single Xeon system is cost effective, and if You're willing to spend the extra cash on a dual socket mobo, instead of purchasing a single socket one, You can upgrade later to a second CPU. I'll make sure to get a motherboard with Thunderbolt 3 and the latest and fastest USB revision.

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

For the longest, longest time, Avid Media Composer was "core agnostic". It barely understood how to use them, and when it was redesigned to start using them, it was still weak.

As of many recent innovations from the Avid Architecture and Media Composer engineering teams (yes they are separate), that has all changed. Take a look at the data in the blog above. If that doesn't answer all your questions, reply back below. If I can answer more, I'll try. If not, I'll push questions at the Avid team and see if they can answer them.

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

From what Luca says, W1 (2 CPUs with 4 cores each), will outperform W2 (1 CPU with 8 cores). Bruno somewhat corroborates this, through the edtra resources that come with a second CPU. Chris' blog offers a more in depth, under the hood glimpse to the evloution of Avid Media Composer, from "core agnostic" to the more cores the better - in fact, the more everything the better, also mentioning the evolution o the software's architecture towards the GPU - a factor that I left out the original post and goes on system resources sucha memory cache allocated on RAM. Yet it doesn't hint to an answer.

You were right Chris, I do have some questions and more variables to the equation that I tried to keep simple. Here they go.

CPU speed was not taken into account. Let's bring them in. Generally CPUs with less cores have higher base clock speeds, which leads to my first question: What is the benefit of faster CPU? For example: tipically, te processing of exporting to MP4 is handled by a single core, which means it's efficiency is directly related to the base clock speed and turbo speed. Is this the way MC exports? CPUs with more cores have bigger cache sizes. Again, wich is better: a bigger cache, or two smaller ones?

As i said, GPU was a bit overlooked in my original post. Again, as with CPUs, what would be bettter, a single GPU with X GB VRAM, or two GPUs with X/2 GB VRAM? Let's not forget the othe specs, such as number or cores, mermory interface and bandwith (don't include monitor support. The main concern is processing power).

RAM, the more the better, we know, but how to configure it? Is it better to have X GB distributed by Y channels, or by 2Y channels? In a dual CPU scenario, how should it be setup?

And this brings us back to the original question. The purpose is not to find a specific system for a specific need, being that a bigger raster, a simple cut, effects, or track counts. The idea is to understand how does MC uses the resources avilable, or as Chris put it "How Avid Media Composer Uses a Computer". Let's dive in this topic more in depth.

For that and to help us reach a more objective answer, let's consider the example of the pair of workstations: W1 and W2. Analyse the specs, taking all the above into account, knowing both will be performing the same tasks.

From that premise, let's try to answer the questions above in order to answer the basic overall question: which of these workstations performs better, W1, or W2?

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

let's try to answer the questions above in order to answer the basic overall question: which of these workstations performs better, W1, or W2?

I suspect there's never going to be a definitive answer to this question as it's a constantly moving target.

As new builds of software come along, developers will tweak the code to exploit the different capabilities of the various components in modern workstations. At each stage in this development, the weakest link in the chain will be exposed and it will encourage further hardware development of those components.

You might be interested in the following tests done by Puget Systems, which is basically confirming the growing belief that dual Xeon systems aren't necessarily the fastest for the sort of work done by media professionals. A lot of people are now starting to go to Intel i9 or Threadripper CPUs with high clock speeds and lots of cores, together with a high-end GPU and loads of memory.

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

I suspect there's never going to be a definitive answer to this question as it's a constantly moving target.

Quite true Bruno!

Howevver, since I'm beginning my design right now, I'm interested in knowing the present state of Media Composer. The future will always be unknown, so, as important as it may be, it looses relevance when you have to implememt a solution. Therefore, one has to play with what's available at the moment.

That being said, the tests with Premiere (thanks for sharing them) illustrate how it handles hardware and by the results, dual Xeon don't pay off. The point here is to figure out how Avid Media Composer harnesses the hardware, at the moment, since the develpoment philisophy may differ in many ways, so the questions still remain.

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

Its an interesting topic but for MC I suspect the differences are relatively small. Avid has always somehow managed to produce similar performance results depsite hardware differences. Some would argue thats achieved by under using resources and tahts why other systems can out perform on the same hardware. Talk to anyone using Premiere about their playback engine and its smooth results with formats MC has to transcode to cope with.

So using current tech I think the variatuion in performance will be marginal and probably vary based on the task being tested.

We probably come back to the discussions on buying off the shelf systems and build your own. An edge can often be had with the best of the best configured in just such a way but its also a gamble on stability. For many a HP workstation is the sensible choice and then the permutations become a lot less.

ACI Moderator. I'm not employed by Avid or work for them. I just do this in my spare time. Normally using the current Media Composer version on My...
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Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

I've done some extensive testing of my own with processor speeds. Essentially, racing computers against themselves and each other. I have SO many different configurations of Avid Media Composer systems at my disposal, that it simply became a hobby (if you will).

Here's what I arrived at. One time, about 2 years ago (so we're talking about the early MC8 versions) I raced two mac mini computers against each other. W1 was a 2012 2.5 i5 with 8GB RAM. W2 was a 2014 1.4 i5 with 8GB RAM. For all serious intents and purposes, identical computers with very different processor speeds being the only notable difference.

I took the exact same Avid Media Composer project, which was running on an external LaCie D2 Quadra (4TB 7200rpm) 1080p23.976 with DNxHD36 media (also on the same drive).

Hitting play was exactly the same on both computers. Zero difference in lag from the spacebar to the playback. Zero difference in the smoothness of playback. Zero difference in scrolling around the timeline.

Why? Because it was all rendered DNxHD managed media.

I then, in the same project, loaded a similar sequence that was all AMA Linked media.

Whammo. Immediate issues with the 1.4 i5 machine. Also issues with the 2.5, but not as bad. Note - the AMA media was a really chewy H.264 (I say "chewy" in reference to eating a steak - sitting there chewing on one mouthful forever), and there was also some Avid SD 1:1 10-bit NTSC media in there.

Next as part of my test, I went back to the DNxHD media sequence, and then opened up Photoshop, Dropbox syncing, Safari with a few tabs open, and the Activity Monitor. On both machines, the Avid playback was tolerably fine, but Safari pages took WAY longer to open on the 1.4 machine.

NOW...

On the flipside, as you know the 2014 trashcan mac pros were released a few years ago with four original configurations. The quad core which was total garbage, the 6-core which was the minimum qualified to run Avid, the 8-core and the 12-core. Everyone (myself included) went and bought the 6-core because its processor speed was the fastest. The goons who bought the 12-core were all sorely mistaken in the Avid world... right?

Only for about a year. Then, as of MC8.3 (...I think...???) the core components of Composer's underlying architecture began to change dramatically towards core usage. All of a sudden I started seeing a marked increase from my friends who were running their 12-core systems, while I saw no change on my end.

So the looooong answer (sorry about that) is that there is no longer an ideal system, and that economics can truly play a helpful role in deciding on what to build. Personally, I'm pretty sure I'm abandoning all my Macs this year. The HP systems are just waaaay too good nowadays, and the macs are left in the dust.

Case in point: I recently raced a brand new fully loaded iMac and a brand new fully loaded z840. Both were tasked with crunching the exact same 55-minute long DNxHD145 QuickTime file through Sorenson Squeeze's standard YouTube 1080p template. The iMac was done in 107 minutes. The HP was done in 41. When you deal with as much media as I do on national PBS documentaries, that's a week's worth of difference.

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

Personally, I'm pretty sure I'm abandoning all my Macs this year. The HP systems are just waaaay too good nowadays, and the macs are left in the dust.

pierreh:

Sad but true, and it's not the pathetic iMac Pro that's going to bring us back to Apple.

I did that last year, after 22 years working with the Mac. The problem isn't just the hardware iteslf, but the OS lost stability, smoothness and became very resource hungry. I too switched to HP.

About iMac Pro, I didn't have a chance to test it yet, but there's the upgradability issue. Comparing systems with same specs, however the iMac Pro is cheaper, specially if you consider it already comes with one monitor. I did this comparison las December just for fun.

Anyway, back to the topic, let me organize what's been said so far. Please do correct what might be wrong.

My only doubt remains with CPU. Is there a real impact on dividing a certain number of cores by 2 CPUs, or is having them in 1 CPU preferable?

What am I thinking regarding this?For the same number of cores, dual CPU configurations can be dramatically more expensive, although they allow for greater clock speeds and cache sizes, RAM and PCI slots. Single CPU configurations are cheaper.

So, now it all comes down to knowing how Avid Media Composer handles CPU processing. Does it take advantage of more than 1 CPU, or not (as it happens with GPU), or if it is agnostic.

Re: Single CPU with X Cores vs. Dual CPU with X/2 Cores

So, now it all comes down to knowing how Avid Media Composer handles CPU processing. Does it take advantage of more than 1 CPU, or not (as it happens with GPU), or if it is agnostic.

I suspect that looking at MC in isolation isn't really going to give very meaningful results. I think it was certainly the case that historically, Avid was not written to be multi processor aware and nothing I've read recently seems to suggest that this has changed. However, MC makes calls to other programs at certain times which may benefit from more processors and cores, such as some of the more modern 3rd party AVX effects. So, just for basic editing (cutting shots onto a single video layer) there really isn't going to be much benefit from dual processors. Once you start adding nested layers and lots of Boris effects the benefits of having dual processors with a number of cores might be better than one processor with the same core count. It's really down to the software designers of the plugins rather than the Avid code. It's also likely that individual effects in a collection like Boris Continuum will ulilize processors/cores differently from each other.

It's also worth remembering that within the Windows OS, there are many processes running in the background. Some of these are integral with Avid's operation, others will have no bearing on MC and will only impact on performance if they happen to be executing some unrelated task which consumes some of the CPU cycles that MC could do with. If these executables are dual processor aware, it's possible they can free up more cycles from the 1st CPU for Avid to use. This is particularly true of disk operations, which is why hardware RAID controllers (and the old SCSI boards) often give better overall performance. These 'intelligent' controllers take over the task of managing the transfer of data, leaving the CPU free to attend to the demands of other software.

So what I'm really saying is that it's really hard to give a definitive answer to the original question for all situations. If you're really stretching the limits of the system with high rez media and lots of multilayer effects, then there is good reason to believe that having dual processors will have benefits. What these benefits will be will vary between the type of effects you choose and how the the software designers have implemented the code to deal with multiple CPUs.